I've just gotten the Kindle PW2, v5.4.3.2. I'm trying to install the collection manager on it, but it says the version isn't supported. I tried downgrading to version 5.3.5 and 5.3.1 both, including amehos link (Once I translated it

) but it won't downgrade. Any suggestions? Keeping in mind that I'm an extreme newbie. Thank you!